Problem: Haruka hiked several kilometers in the morning. She hiked only $6$ kilometers in the afternoon, which was $25\%$ less than she had hiked in the morning. How many kilometers did Haruka hike in all?
Haruka walked $25\%$ fewer kilometers in the afternoon, so she walked $100\%-25\%={75\%}$ as many kilometers in the afternoon as in the morning. She walked ${6}$ kilometers $(\text{km})$ in the afternoon. Percent means per hundred, so ${75\%}$ is equivalent to ${\dfrac{75}{100}}$ which is also equal to ${75\div 100}$. ${75\div 100 = 0.75}$ To find how far Haruka hiked in the morning, we need to answer, ${6\,\text{km}}$ is ${75\%}$ of what distance? We can rewrite that question as an equation. $\begin{array}{ccccc} {6\,\text{km}}&\text{is}&{75\%}&\text{of}&\text{what distance}}\\\\ {6}&=&{0.75}&\times&?} \end{array}$ Let's solve for the unknown distance. $\begin{aligned} \dfrac{{6}}{0.75}&=\dfrac{{0.75}\times?}}{0.75}\\\\ 8}&=?} \end{aligned}$ Haruka hiked $8\,\text{km}}$ in the morning and ${6\,\text{km}}$ in the afternoon. How far did she hike in all? Haruka hiked a total of $8\,\text{km}}+{6\,\text{km}}=14\,\text{km}$ in all.